The present invention relates to a governor for an automatic transmission of a vehicle.
FIGS. 3 and 4 show a RN4F02A type automatic transmission of Nissan Motor Co., Ltd.
The unit of FIGS. 3 and 4 is an automatic transaxle for a front engine front wheel drive vehicle. This transaxle includes a converter housing 1, a transmission case 2, a torque converter 3, a mechanism 4 of the transmission, a reducton shaft 5, a differential case 6, a governor drive gear 7 fixed to the differential case 6, a governor shaft gear 8 in mesh with the governor drive gear 7, a speedometer pinion gear 9, a governor shaft 10, a governor case 11, a governor valve 12, and a governor cap 13. The gears 7 and 8 are designed so that intermeshing between the gears 7 and 8 produces a component of a force, acting on the governor shaft 10 in the direction toward the governor valve 12 when the vehicle is driven in the forward direction.
As shown in FIGS. 4 and 5, a stopper bolt 14 is provided for preventing the governor shaft 10 from being extracted. The governor shaft 10 is formed with an annular groove 10a for receiving the stopper bolt 14. The stopper bolt 14 is inserted from the outside of the governor case 11 through a seal washer 15 into the annular groove 10a. A similar structure is show in U.S. Pat. No. 4,559,842.
However, this conventional structure requires the annular groove 10a of the governor shaft 10, the stopper bolt 14 and the seal washer 15. Furthermore, a middle portion 14a of the stopper bolt 14 must be formed into a shape having a square cross section, and the surfaces of the annular groove 10a and the square middle portion 14a of the stopper bolt 14 must be hardened by heat treatment in order to meet the problem of wear and abrasion.
Therefore, the conventional structure is disadvantageous in that the number of components parts, and the number of steps for producing the structure are greater, and accordingly, the production cost is increased.